From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752349AbcE1M1x (ORCPT ); Sat, 28 May 2016 08:27:53 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:34059 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751894AbcE1M1v (ORCPT ); Sat, 28 May 2016 08:27:51 -0400 From: Minfei Huang To: bp@suse.de, pbonzini@redhat.com, luto@kernel.org, hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Minfei Huang Subject: [PATCH 3/3 V2] pvclock: Get rid of __pvclock_read_cycles in function pvclock_read_flags Date: Sat, 28 May 2016 20:27:43 +0800 Message-Id: <1464438463-8485-1-git-send-email-mnghuan@gmail.com> X-Mailer: git-send-email 2.6.3 In-Reply-To: <1464329832-4638-3-git-send-email-mnghuan@gmail.com> References: <1464329832-4638-3-git-send-email-mnghuan@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is a generic function __pvclock_read_cycles to be used to get both flags and cycles. For function pvclock_read_flags, it's useless to get cycles value. To make this function be more effective, get this variable flags directly in function. Signed-off-by: Minfei Huang --- v1: - Get rid of __pvclock_read_cycles according to Andy's suggestion --- arch/x86/kernel/pvclock.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c index 7f82fe0..06c58ce 100644 --- a/arch/x86/kernel/pvclock.c +++ b/arch/x86/kernel/pvclock.c @@ -61,11 +61,14 @@ void pvclock_resume(void) u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src) { unsigned version; - cycle_t ret; u8 flags; do { - version = __pvclock_read_cycles(src, &ret, &flags); + version = src->version; + /* Make the latest version visible */ + smp_rmb(); + + flags = src->flags; /* Make sure that the version double-check is last. */ smp_rmb(); } while ((src->version & 1) || version != src->version); -- 2.6.3